In this Getting Started, we will create a console application running in .NET 6 or 8 that will read a value from an OPC server, and display the value on the console.

Prerequisites

• Supported operating system: Linux, macOS or Windows.
• .NET 6 or 8 SDK: 
  • Linux instructions,
  • macOS instructions,
  • Windows instructions.
• A text editor or code editor of your choice.
• Internet connection with access to www.nuget.org (for downloading NuGet packages) and www.opclabs.com (for connection to the public OPC UA and OPC XML-DA servers).
• Note that for this Getting Started, you DO NOT need to install OPC Data Client (using the Setup program), as the necessary component packages will be pulled from the Internet.

Console Application to Read Value from OPC Unified Architecture Server

1. Open a command prompt.

2. Create a folder named Hello and navigate to the folder.

3. Type the following: dotnet new console. This command creates a project file (Hello.csproj) and a main program file (Program.cs).

4. Type the following: dotnet add package OpcLabs.QuickOpc. This command adds OPC Data Client package reference to the project file.

   The above command actually adds a reference to the package corresponding always to the very latest OPC Data Client version. If you want to be sure that you referencing a package for OPC Data Client 2024.2, use dotnet add package OpcLabs.QuickOpc --version 5.81 command instead.

5. Using a text editor, add following code to the beginning of the Program.cs file:

   using OpcLabs.EasyOpc.UA;
   

6. In Program.cs, replace the body of the Main method by following code:

   var client = new EasyUAClient();
   object value = client.ReadValue(
       "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer",
       "nsu=http://test.org/UA/Data/;i=10853");
   Console.WriteLine(value);
   

7. Save the changes to Program.cs.

8. In the command prompt, type dotnet run. This will build and launch the program. The value will be read from the OPC server and displayed on the console.            

Console Application to Read Value from OPC XML-DA Server

1. Open a command prompt.

2. Create a folder named HelloXml and navigate to the folder.

3. Type the following: dotnet new console. This command creates a project file (HelloXml.csproj) and a main program file (Program.cs).

4. Type the following: dotnet add package OpcLabs.QuickOpc. This command adds OPC Data Client package reference to the project file.

   The above command actually adds a reference to the package corresponding always to the very latest OPC Data Client version. If you want to be sure that you referencing a package for OPC Data Client 2024.2, use dotnet add package OpcLabs.QuickOpc --version 5.81 command instead.

5. Using a text editor, add following code to the beginning of the Program.cs file:

   using OpcLabs.EasyOpc.DataAccess;
   

6. In Program.cs, replace the body of the Main method by following code:

   var client = new EasyDAClient();
   object value = client.ReadItemValue(
       "http://opcxml.demo-this.com/XmlDaSampleServer/Service.asmx",
       "Dynamic/Analog Types/Double");
   Console.WriteLine(value);
   

7. Save the changes to Program.cs.

8. In the command prompt, type dotnet run. This will build and launch the program. The value will be read from the OPC server and displayed on the console.